Why is My Fence Gate Sagging?

Maxwell Wiczek
Nov 14
2 min read

... Part 2!

If you’ve noticed your fence gate dragging, scraping the ground, or the latch no longer aligning, chances are it’s sagging. A sagging gate is both annoying (hard to open/close), inconvenient and a red flag that something in the structure is out of true. Let’s break down the why, then the how (the fix), so you’ll understand what’s going on and how to address it.

Common Causes of Sagging

1. Gate Post has Shifted or is Unstable

The gate is only as good as the post it hinges to. If the post is loose, rotten, leaning, or twisted, that undermines everything.
Soil movement, frost heave, wet ground, or poor footing around the post can allow it to move.
If the hinge side post leans or pulls outward (especially under the weight of the gate), the far side will drop.

2. Gate frame itself is out of square / weak

Even with a solid post, the gate can sag if its frame has warped, the screws are loose, or the structural braces are missing/damaged.
Good bracing is essential: for example a diagonal brace transfers the weight and keeps the gate from “drooping.”
On larger gates, sag can happen simply because the span is wide, making the latch side drop under its own weight unless supported.

3. Hardware / Hinge issues

Loose hinge screws, rusted hinges, or hinges mounted incorrectly can allow the gate to sag or pivot slightly.
Over time, the hinge screws may pull out, especially if the post has shifted. That movement compounds sag.

4. Gate is too Heavy (or load is mis-applied)

A very heavy gate (wood, dense materials) increases the stress on the post, hinges, and frame. If it isn’t well-designed/braced, weight will cause sag.
Also, if the gate swings on soft ground, drags, or hits the ground every cycle, that extra friction/drag will exacerbate sag.

How to Diagnose Your Gate

Before you jump into repairs, take a systematic look:

Check the post: wiggle it. Does it move at the base or up top?
Use a level or straight-edge: is the post plumb (vertical)?
Measure the gate: are the diagonals equal (top left to bottom right vs top right to bottom left)? If not, the gate is out of square.
Inspect hinges and screws: are they tight? Are hinges bent or worn?
Look at the gap beneath the gate: is it wider on one side? Is the latch side lower than the hinge side?
Check for “given” in frame: is there a diagonal brace present? Has the frame twisted or warped?